Scleroscope



Feb. 6, 1923,

' G. WIRRER ET AL.

scLERoscoPE. F|`LED MAR. 29, 1.921.

Patented Feb.. tl, i923.

Gorrrsun winnen. or rnmwrrmm, NEW JERSEY.-

aa 'n VQ @tu Vi ,f tirant '"6 1 aiallllidllq irritante ann anunciaron entraron IVOYER, @E ALLENTWN, PEQ'IISYLVANLFL, ASSGNRS TC) ENTERNATlINL MOTOR COMPANY, Gl NEUF YORK, l. Y., l GOEPQBA'EIOE Ol? DELA'WiRE SCLEROSCFE.

application inea risticii ze To all whom t may concern- Be it lrnown that we, Gorrrninn lvlfrnnnn, a citizen of the Swiss Republic, and innrwd TON CLrNroN Morne, a citizen ci the United States, residin, respectively, in Plainfield.,

in the State o'i New Jersey, and in Allen town, in the State or' Pennsylvanial have invented certain new and useful .improvement-s in Scleroscopes, ot which the following aspecication, reference being had to the accompanying drawing, forming a part hereof.

rllhis invention relates to an improved scleroscope, that is, a machine lor testing the hardness ot materials and particularly of metals.

Machines ot' the same general character with which the present improvements are concerned have been devised and employed with some degree of success in scientiiic laboratories for some time. Such machines, however, generally have relied upon rather` complicated operating devices for the testingl hammer which iave been actuated by pneu1 matic means. The result has been a very complicated, delicate and expensive machine, lacking somewhat in the desired da grec of accuracy and by no means unvariable in its readings, degrees or error being consequently introduced by reason of the very nature of the control devices employed. The present invention has for its general object to improve machines for the purpose described by substituting` ior the complicated and uncertain pneumatic control devices heretofore employed a positive mechanical release tor the hammer ot a very simple and inexpensive character. The control devices now proposed being of a positive iechanical nature insure the instant release of the hammer with unvarying certainty unser corresponding conditions, thereby eliminat ing one source of error characteristic ot pneumatically operated devices.

Another source of error which has been present in scleroscopes as known has been the pressure vacuum set up by the railing hammer within its indicating tube. By the present improvements it is assured that the hammer shall always fall-freely in a normal atmosphere and be subject to equal pressures on its two sides.

Another unsatisfactory feature or known scleroscopes has been thatthe pneumatic deserial no. sacca during each reciprocation ol the controlling element, the hammer being automatically returned to position for a Yfurther reading each time.

Reference is now to be had to the accompanying drawing for a detailed description of one simple embodiment of the improvements, in which drawinglligure l is a view in vertical section ot a fragment or' the improved scleroscope showing` particularly the 'control devices for the Jfalling hammer.

Figure 2 is a view in elevation of a complete machine showing the relation or" parte' and the indicating scale for readings.

Scleroscopes test the hardness of materials by aiording the observer an opportunity toread the extent or rebound or" a hardened hammer when permitted to fall a predetermined distance on to the material to be tested. To obtain accurate readings it is evident that tie control devices l'or releasing the hammer and all ot the associated parts should be oit such character as to bring about a fall under unvarying conditions so that the relative heights ot rebound can be noted by the observer. is shown in Figure 2 the machine comprises generally a base o; on which is supported a vertical transparent tube b, graduated in equal divisions.Il as indicated at c. The material to be tested indicated at d, and is placed under the lower open end or' the tube b to afford a striking base for a hardened hammer e which is permitted to drop 'from the top ot the tube on to the material, its rebound within the tube as noted from the scale readings indicating a certain degree of hardness of the material tested, as compared with other materials, the hardness of which can be tested in the same manner. rlhe present improvements relate particularly to the control devices for eii'ecting the reading, positive and unvaria ble release of the hammer e and permitting it to tall -within the tube in the normal atmosphere and with equal pressures on its two sides. The hammer c is shown as recessed at e and hanged at c2 to receive opposed hoolrs pivoted as at f in the head f2 ot the machine. These hooks while supporting the hammer e in raised position are actuated to release the hammer for its fall. rlhe upwardly extending arms of the hooks f terminate in-cam edges f3 adapted to bear against the inner wall of a hollow steel cone g. By pressing down on this steel cone g it will be evident that the lower ends of the hooks will be brought together for the release of the hammer e. The cone g is normally held in raised position by means ot a spring g. rl`he upper edge of the ring g is engaged by a plunger It mounted to reciprocate in a cylinder z' secured to the head f2 of the inachine. Within the opening in 'the ring g and extended upwardly into the plunger ZL is a tumbler lo having a conical recess in its lower end against which bear the curved ends of the hooks 7?. The action of the tumbler lo on the hooks is to force their lower ends apart so as to hold them in engagement with the retaining flange c2 on the hammer e. The plunger 7L is recessed, as indicated, to receive the end of the tumbler la and also a spring is which constantly presses the tumbler downwardly but yieldingly into engagement with the upper end of the hooks The upper end of the lunger Ii, terminates in a stem it which extends through a central opening e" formed in the upper wall of the cylinder e'. The

stem it may carry on its end a bearing roller h2. The plunger ZL may have its end finished olf with a washer h3 which constitutes a seat and closes off the interior of the cylinder z' against the opening i.

`'llhe upper end of the stem ZL with the roller ZL? rests within an upper cylinder Z which is secured removably on the lower cylinder z' by means of bolts Z. The bore of the cylinder Z has mounted to reciprocate therein a piston m carrying a stem m which extends through the end wall Z2 of the cylinder Z and may have at its eXtreme end a convenient linger button m2 to facilitate manual operation. interposed between the end wall Z2 of the cylinder Z and the button m2 is placed, in the illustrated embodiment, a spiral spring a for holding the piston m yieldingly at the upper end 0f the cylinder Z. The interior of the cylinder Z is open to the atmosphere through an aperture Z3 formed conveniently in the end wall Z27 so that reciprocations of the piston m within the cylinder take place at normal atmospheric pressure. The interior of the cylinder Z is preferably in communication with the interior of the cylinder z' through registering channels Z4, 3, formed respectively in the walls -of said cylinders.

The operation of the machine is positive and insures the release ofthe hammer c the retaining flange e2 and with the material CZ, whose hardness is to be tested, under thelower open end of the tube b, the improved devices provide for the convenient and sharp release of the hammer so that its rebound. can be observed. rlhe lower ends of the hooks are held in engagement with the flange c2 by the pressure exerted on the ripper' ends of the hooks by the springpressed tumbler Za. it this time the spring g acting on the ring g will seat the plunger /t through its gasket a3 on the upper end of the cylinder 'a'. The operator presses the piston m downwardly in the cylinder Z against the action of the spring n by pressure on the stem m. As soon as the piston m overruns the end of the channel Zt, atmospheric pressure in the upper end of the cylinder Z will be permitted to the interior of the cylinder z' and to the interior of the tube Z) through the channel 3. Continued movement of the piston m will bring it in engagement with the roller ZL? and force the plunger ZL downwardly so as to slide the conical ring g along the cam surfaces on the opposed forks so as to press thelower ends thereof together and disengage them from the supporting flange e2 for the hammer e. The release of the hammer is thus effected by posit-ive mechanical devices. The cam will he released quickly and will fall in the tube Z in a normal atmosphere. Its .drop cannot., as in previous devices, result in the creation of a pressure vacuum behind it so as to retard its free drop under gravity. The rebound of the hammer e after striking the material Z will be observed from the scale c. After taking the reading, the operator will release the pressure on the stem m as to permit the spring n to move the piston m upwardly in the cylinder Z. As soon as the piston m overruns the end of the channel Z4 its continued movement will create suction within the tube Z) sufficient to draw the hammer c from the lower end thereof up into engagement with the hooks The hooks will be locked as 1n'efore by the springpressed tumbler 7c. By the operation described it will be evident that upon one complete reciprocation of the piston m a reading will have been secured and the hammer will have been returned to position in readiness for another reading. This simplicity of design. and operation is important and marks an improvement of known devices in which several operations :were necessary to release the hammer and then return it to raised positionfor a further reading.

It will be desirable to limit the downward movement of the piston m while in engagement with the end of the stem ZL since its continued movement might result in undue movement of the `ring g and excessive spreading of the forks f to a point where they might be injured. Such means Jfor limiting the downward movement of the piston m is provided in an adjustable stop screw o which can be threaded in the lower cylinder i and have its end o exposed within the cylinder Z and in such relation to the roller )t2 and the piston m as to arrest the movement ot the latter after predetermined movement of the stem 7L.

The striking characteristics of the improved machine are simplicity ci construction, directness and certainty of operation and unvariable conditions ot release ot the hammer. With these broad objects in mind, it will be understood that the devices are not to be limited to the structural details shown and described herein since a skilled mechanic can, as to each ot the elements, substitute equivalents therefor or change their details according to circumstances without modifying the modus operandi of the machine.

lNe claim as our invention:

l. ln a machine for testing the hardness or' materials, a hammer, an open ended tube in which the hammer moves, devices for supporting the hammer releasably in raised position in said tube including a hoolr engageable with the hammer, a cylinder carried on the tube and communicating therewith through an air port, a manually operable piston reciprocable in the cylinder and means engageable the piston and with the hook Jfor moving the latter out of engagement with the hammer, said piston being adapted to overrun said air port before release oit the hammer to place the tube in communication with the atmosphere.

2. ln a machine tor testing the hardness ot materials, a hammer, an open ended tube in which the hammer moves, devices for supporting the hammer releasably in raised position in said tube including a hook engageable with the hammer, a cylinder carried on the tube and communicatingtherewith through an air port, a manually operable piston reciprocable in the cylinder and means engageable by the piston and with the hook for moving the latter out of engagement with the hammer, said piston being adapted to overrun said air port berore release of the hammer to place the tube in communication with the atmosphere, and said piston in its return movement being adapted to overrun said port and draw the hammer up into engagement with the retaining hoolr by creating suction within the tube.

3. ln a machine for testing the hardness or materials, hammer, an open ended tube in which the hammer moves, hooks for supporting the hammer releasably in raiser position, a cylinder supported on the tube, a plunger mounted -reciprocably within the cylinder and co-operating with means tor swinging the hoolrs to the hammer, a second cylinder mounted on said iirst cylinder but in communication therewith through communicating channels., a stem on the plunger extending through the end wall of the first named cylinder into the second named cylinder', a piston mounted reciprocably within the second named cylinder and having a stem for manual operation ot the piston, said piston being subjected on its rear side to atmospheric pressure and adapted to overrun the said channels to place the tube in communication with the atmosphere before engaging the stem ot the plunger tor release or the hoolrs.

le ln Aa machine ior testing the hardness of materials, a hammer, an open ended tube in which the hammer moves, hooks tor supporting the hammer releasably in raised position, a cylinder supported on the tube, a plunger mounted reciprocably within the cylinder and co-operating with means for swinging the hoolrs to r-elease the hammer, a second cylinder mounted on said Aiirst cylinder but in communication therewith through communicating` channels, a stem on the plunger extending through the end wall of the iirst named cylinder into the second named cylinder, a piston mounted reciprocably within the second named cylinder and having a stem tor manual operation oi' the piston, said piston being subjected on its rear side to atmospheric pressure and adapted to overrun the said channels to place the tube in communication witn the atmosphere betere engaging the stem or the plunger for release oi' the hooks, and an adjustable stop mounted within the second named cylinder to limit the movement ot the piston after engagement with the stem..

This specification signed this 30th day oi September, A. l). i921.

eo'rrrmnn winnen.. animieren cerraron Morne. 

